1. Field of the Invention
This invention relates a reference beam detecting apparatus for detecting a reference laser beam emitted from a laser unit to determine the height of construction. It also relates to a reference beam detecting apparatus comprising a data display section for displaying its angular displacement relative to a laser unit and a data display section for displaying the distance between itself and the laser unit.
2. Prior Art
Transits and levels are conventionally used on building sites and other construction sites to determine a reference plane or a reference height. Recently, laser levels designed to emit laser beams in the form of a sector to define a reference plane are getting popular along with rotary laser units designed to emit a rotating laser beam to define a reference plane. Such a laser unit is typically used in combination with a reference beam detecting apparatus for receiving the emitted laser beam to define a reference plane or a reference height. The construction personnel puts a mark at each appropriate reference position to reflect the indication displayed on the display section of the reference beam detecting apparatus for that position.
Thus, known reference beam detecting apparatus are replacing transits, levels and other surveying apparatus to determine or select a reference height. However, actual construction works, if simple, involve a number of different surveying operations including determining the distance of a spot from a reference position, seeing the angle of a bent wall, finding the gradient of a ditch or a drain pipe and so on, that require the use of transits and levels in addition to the reference beam detecting apparatus to make such operations more cumbersome than before.
In view of the above identified problem of known reference beam detecting apparatus, it is therefore an object of the present invention to provide an improved reference beam detecting apparatus that can carry out various surveying operations including determining the distance of a pot from a reference position, seeing the angle of a bent wall and so on to significantly reduce the time required for a construction work.
Another object of the invention is to provide a reference beam detecting apparatus that can determine the gradation of a ditch, a drain pipe or some other object of construction.